Juvenile idiopathic arthritis and the temporomandibular joint : a case-control study of magnetic resonance imaging findings in relation to clinical and psychosocial factors.

AIM: In juvenile idiopathic arthritis (JIA), the temporomandibular joint (TMJ) is a particularly challenging joint to assess both clinically and with imaging. The aim of this article is to investigate TMJ magnetic resonance imaging (MRI) findings in relation to clinical and psychosocial factors in patients with JIA and healthy individuals related to TMJ arthritis in JIA. MATERIALS: In total, 45 patients (6-16 years) with JIA and 16 healthy age- and sex-matched controls were examined according to the diagnostic criteria for temporomandibular disorders (DC/TMD). The subjects answered questionnaires about psychosocial factors (pain intensity, pain-related disability, depression, stress, catastrophising, pain locations, and jaw function) and underwent bilateral MRI of the TMJ. RESULTS: There were no significant differences between JIA patients and healthy individuals in any of the TMJ MRI findings. Moderate/severe changes among JIA patients were found only for effusion, synovial thickening, condylar flattening, and erosion, with no moderate/severe changes in healthy individuals. In JIA patients, orofacial pain intensity was related to TMJ bone marrow oedema, and pain in jaw muscles during jaw function was related to TMJ bone marrow oedema and erosion. There were no significant correlations between psychosocial aspects and MRI findings. CONCLUSION: This study indicates a substantial overlap of TMJ MRI findings in both the inflammatory domain and the damage domain between JIA patients and healthy individuals. In JIA patients, the inflammatory MRI sign of bone marrow oedema seems to influence orofacial pain intensity